Pulleys for conveyors and mountings



Aug. 8, 1967 J, D. RlEsER PULLEYS FOR CONVEYORS AND MOUNTINGS Filed March 23, 1965 4 Sheets-Sheet 1 Vinh.

Aug. 8, 1967 J. D. RlEsER FULLEYS FOR CONVEYORS AND MOUNTINGS 4 Sheets-Sheet 2 Filed March 23, 1965 Aug. 8, 1967 J. D. Rui-:SER

PULLEYS FOR GONVEYORS AND MOUNTINGS 4 Sheets-Sheet 5 Filed March 23, 1965 All@ 8, 1967 J. D. RlEsl-:R 3,334,523

PULLEYS FOR coNvEYoRs AND MOUNTINGS Filed March 23, 1965 4 Sheets-Sheet 4 United States Patent 3,334,523 PULLEYS FOR CONVEYORS AND MOUNTINGS .lohn D. Rieser, 693 Mission St., San Francisco, Calif. 94105 Filed Mar. 23, 1965, Ser. No. 442,042 14 Claims. (Cl. 74-230.3)

This invention relates to wide face pulleys for various types of belted conveyor systems, wherein the pulley includes a central tubular member with extensions beyond each end of the pulley and formed to substantially eliminate introducing bending moment stresses into diiferent type shaft elements by pulley loadings, whether the pulley forms a belt conveyor driver pulley with a rotating shaft or as a tail, takeup, snub or bend pulley with a rotating or a stationary shaft.

An object of the present invention is to provide a selfcontained conveyor pulley formed of a cylindrical rim, radial web means and a central tubular member, wherein the web means being secured to an internal part of the rim and an external part of the tubular member, with the tubular member extending axially through and beyond the rim while supporting at each its end portions an antifriction bearing for 'a nonrotating support shaft.

Another object of the present invention is to provide a self-contained conveyor pulley as above wherein, the nonrotating support shaft projects beyond each end of the tubular member with screw threaded means for securing the shaft to its support apparatus.

Another object of the present invention is to provide a self-contained conveyor pulley formed of a cylindrical rim, radial web means and a central tubular member wherein, the web means being secured to an internal part of the rim and an external part of the tubular member with the tubular member extending axially through and beyond the rim with a bore at each its end portions for securing thereto iixedly of a drive shaft for driving the pulley. j

Another object of the present invention is to provide an operable combination of a self-contained conveyor pulley together with a cylindrical rim, radial web means and a central tubular member of which the web means being secured to an internal part of the rim and an external part of the tubular member with the tubular member extending axially through and beyond the rim While sup porting at each its end portions an anti-friction bearing for the shaft that extends through and beyond the tubular member for engaging the support facilities in adjacency to each end of said tubular member and thereby forming a means to substantially eliminate a lever arm that would cause introduction of bending forces into the shaft by the pulley loads.

Another object of the present invention is to provide an operable combination of a self-contained conveyor pulley together with a drive shaft and journal support facilities wherein, the pulley being formed of a cylindrical rim,

radial web means and a central tubular member of which i the web means being secured to an internal part of the rim and an external part of the tubular member with the tubular member extending axially through and beyond the rim with a bore at each its end portions for securing thereto iixedly the drive shaft which extends axially through and beyond the tubular member for engaging journal support facilities in adjacency to each end o-f the tubular member and thereby forming a means to substantially eliminate a lever arm that would cause introduction ofvbending forces into the drive shaft by the pulley loadings disposed intermediate the journal support facilities.

Other more specific objects and advantages Will appear from the following description of the illustration of the embodiment of the present invention.

In the drawings accompanying and forming a part hereof.

FIGURE 1 is a side View partly in section in free position of my self-contained conveyor pulley arranged with a stationary shaft for application as a conveyor tail or takeup pulley.

FIGURE 2 is an enlarged view similar to that of the FIGURE 1 of an end portion showing its operable mounting therein my takeup FIGURE 3.

FIGURE 3 is a side view of my takeup.

FIGURE 4 is an end view at the adjusting end of my takeup FIGURE 3.

FIGURE 5 is an end View similar to that of the FIG- URE 4 but, of the opposite end of my takeup FIGURE 3.

FIGURE 6 is `a side View similar to that of FIGURE 1 but, arranged with a drive shaft.

FIGURE 7 is an enlarged view similar to that of the FIGURE 6 of an end portion showing its operable journal mounting.

FIGURE 8 is a side view similar to that of the FIGURE 1 but, arranged for application as a conveyor snub or bend pulley.

FIGURE 9 is an enlarged view similar to that of the FIGURE 8 of an end portion showing its operable mounting onto a conveyor Stringer.

FIGURE 10 is an end view taken in direction of the line 1tl-10, FIGURE 9.

FIGURE `11 is an end `view` partly in section taken on the line 11-11, FIGURE 6'.

Referring to the FIGURES 1, 6 and 8 showing in each case a side view of my conveyor pulley. Generally, this pulley is formed of the cylindrical rim indicated by the numeral 22, the two radial webs 23 and the central tubular .member 24, all hereinafter described.

The FIGURES l and 2 show arrangement of the pulley for conveyor tail or takeup pulley with a stationary shaft. The `arrowed line 25 represents the diameter of the pulley, while the arrowed line 26 represents the face width of the pulley, which in conveyor practice is two or more inches greater than the normal width of the conveyor belt or size, not here shown, the face 26 is shown straight however, it may be made crowned if so desired. The radial web means 23 are here shown as flat discs, having externally a series of ribs 27, only one being shown at each web means. Each of these ribs 27 are welded to an inner surface of the rim 22 and the outer surface of the central tubular member 24 and the web means 23, these weld ments are not here shown. While the radial web means are also Iwelded to an internal portion of the rim 22 and external portions of the central tubular member 24 as at 28, all to form a single self-contained rigid pulley structure. And with particular reference to the FIGURE 2, which shows an enlarged section at each end of the central tubular member to show the mounting of a takeup pulley with a nonrotating shaft 29. Each end of the central tubular member is bored for a bearing 30 and the seal members 31 and 32 which are all held in place by the snap ring 33 and the shoulder 34. The shaft 291 includes the bushing 35 lwhich has external diameters to form a shoulder S9 and to match that of the internal diameter of the bearing 30' and an internal diameter to match that of the shaft 29 and held in place on the shaft by the setscrew 36. The bearing 30 of standard form includes its one way seal 37. One end of the bushing projects slightly beyond the end of the member 24- and abuts a surface of the takeup frame 39, hereinafter described, while the shaft 29 projects beyond this end of the bushing and for support purposes engages the bore 58 of the takeup nut 38 and an outward end of the shaft 29 includes screw threads and the locknut 40 so that in tightening up of this locknut causes clamping of a takeup adjustment while the takeup frame is mounted on an upper face of a conveyor stringer shown by means of dash lines of which both the adjustment and the conveyor stringers are hereinafter described. Each end of the shaft 29 includes the transverse notch 41 for the adjusting screw 45 and the grease fitting 42 as well as the apertures 43 for delivering of lubricant into the grease pocket 44 for lubrication of the bearing 30.

Now assuming that the pulley together with its shaft 29 and a spaced pair of takeup units having been properly mounted operably, it is to be particularly noted that the pulley load disposed intermediate the pair of takeup units is supported by the shaft 29 through the pair of bearings 30, each of which in turn are disposed within both end portions of the central tubular member 24 that extend beyond the ends of the pulley to a position in adjacency to the nut member 38 of the takeup unit as represented by the arrowed line 45A or moment arm with the following advantages: (1) Referring to the FIGURE 1 the width spacing apart of the takeup units are as represented by the arrowed line 46 and this width 46 relative to that of the spacing apart of the radial web means 23 are independent of one another due entirely to the short moment arm 45A which substantially causes elimination of the shaft 29 flexing, as a consequence (2) provides that the shaft 29 be of material smaller size than would be the case were the bearings 30 or the like disposed at the radial web means as happens to be prior practice concerning the production of wide face conveyor pulleys arranged with a stationary shaft, for then unavoidably shaft flexures take place, with the result (3) that thereof these prior wide face pulley units that have their shaft bearings disposed at each radial web, it is a well established matter that with an increase of the distance between the pulley ends and the takeup nut of the takeup unit and even with an increase in the shaft size unavoidably results in a corresponding decrease in the allowable pulley load. Which is not the case thereof the present invention as it provides having the shaft bearing in an adjacency to that of the takeup nut, consequently, the allowable pulley loadings is unimpaired, resulting in (4) over a wide range of conditions and conveyor sizes .advantageously allows using a given size shaft, owing entirely to substantially eliminating shaft flexure situations, consequently (5) provide use of corresponding smaller size takeup units throughout a wide range of conditions and pulley sizes, that unquestionably results in (6) cost savings, as a given development may be applied over a wide range of pulley sizes and conditions. (7) And further in the central tubular member 24 being of size to accommodate the outside diameter of the shaft bearings 30 readily provides sucient strength to allow using double row type bearings in place of the single row bearings 30 showing the fol! lowing end result (8) that the pulley be readily included into conveyor systems handling heavy class commodities while retaining its small shaft size. (9) In that the present invention provides a means for applying the same size shaft over a wide range of conditions, conveniently provides simple inexpensive methods to prevent rotation of the shaft 29 `and to rigidly clamp a takeup adjustment when operably installed. Of which to prevent the shaft rotating arranged for the lower portion of the adjusting screw 45 to extend through the transverse notch 41 and to rigidly clamp a takeup adjustment is by screwing in of the nut 40 at each end of the shaft 29, thereby providing a rigid tail or takeup pulley combination, none of which being feasible or provided thereof prior conveyor pulley developments. (10) Heretofore to provide conveyor tail or takeup pulleys with bearings bolted to the pulley end Webs for a nonrotating shaft, had to be made to order, for the very valid reason that the size of the required shaft and corresponding size self-aligning anged cartridge bearing units was always an unknown factor prior to the receipt of a precise order. Therefore the manufacturer was not in position to bore these i end webs for the body portion of these costly flanged cartridge bearing units that extend through these web bores. Which also applies to the necessary bolting connections required to fasten their bearing units onto the web members. Then further the required shaft `and pair of takeup units must also be made to order. All of which involves very costly manufacture procedures as well as being very bothersome.

In that the present invention provides means to substantially eliminate shaft ilexure situations furnishes desirable feature whereby conveyor tail or takeup pulley with bearings and shaft may be safely produced in economical colume for stock purposes, from which the different size complete units can readily be marketed without the necessity of their having to be made to order. And the very same desirable production features pertains as well to the shafts and takeup units.

(ll) Then the present invention complies with the established standards concerning gauge spacings of the conveyor stringers for various size conveyor systems.

Referring to the FIGURES 2 and 3 showing a side and .a sectional end View of my takeup unit of which the frame 39 is a piece of a structural channel and having through its web the slotted hole 43 of which the length of the arrowed line 49 represent the take-up travel for the takeup nut 38. To one end of the frame 39 is welded the angle clip 50 and to the opposite end is Welded the bar 51 with the pads 52 (these Weldments are not shown). On the center line 47 of the adjusting screw both the clip 50 and the bar 51 are provided with a journal bore for the shank portion of the nut 55A and the bushing 54 both of which are secured by pins 55 to the ends of the adjusting screw 45 with their head portions forming a shoulder beyond the outer faces of the clip 5() and bar 51 so as to prevent of endwise movement of the adjusting shrew 45 yet, allow of its being rotated manually. A loose washer 56 extends `about a portion of the nut shank. The adjusting screw 45 having screw threads that threadingly engage corresponding screw threads within the takeup nut 38 so that upon manual actuation of the adjusting screw causes the takeup nut to travel in an axial direction as it is guided by the inner surfaces of the channel frame 39 anges. The takeup nut 38 includes a bore S8 to match the diameter of the shaft 29 to allow of its extending therethrough (best seen at the FIGURE 2), so that upon effecting the above mentioned manual actuation causes corresponding pulley position adjustment. The clip and the bar 51 include the bolt holes 57 for fastening the takeup unit rigidly onto the conveyor structures not shown.

Now referring to the FIGURES 6, 7 and 11, which shows the same pulley as that shown at the FIGURE l but, arranged to provide a conveyor drive or head pulley wherein the shaft revolves with the pulley. And where parts are same as those heretofore described, apply the same numeral and where the change is slight use the same numeral with the prefix The arrowed line 25 represent the diameter of the pulley while the arrowed line 26 represents the face width of the pulley, which in conveyor practice is two or more inches greater than the normal width of the conveyor belt (not here shown). Again the face 26 is shown straight however, it may be crowned if so deseired. The radial web means 23 here shown as flat discs having externally a series of ribs 27 only one being shown at each web means. Each of these ribs 27 are welded to an inner surface of the cylindrical rim 22 and the outer surface of the central tubular member 24 and again these weldments are not shown. While the radial web means 23 are also welded to an internal portion of the rim 22 and external portions of the central tubular member 24 as at 28, all to form a single self-contained rigid pulley structure. And with particular reference to the FIGURE 7, which shows an enlarged section at each end of the central tubular member to show the mounting of a head puplley with a rotating shaft 60, Each end of the central tubular member includes the hub 61 which is welded therein as at 62 and the series of plug welds 63 (FIGURE ll). After which they are bored for the shaft 60 and fitted with -the keys 64 and setscrews 65. The shaft 60 extends beyond each end of the central tubular member 24 for the shaft bearings which are shown by means of a cross 67 and their center line 68 and by means of dash lines indicate the collar portion 66 of this bearing 67 in FIGURE 7. Also the FIGURE 7 indicates by means of dash lines the top flange of a conveyor `Stringer 69 with a plate 70 welded thereto and eX- tending outwardly to which in practice is bolted the base of the bearing 67, while the line 73 represents the gauge line of the stringer. The spot drills 71 are for the collar setscrews. Then at one end beyond the bearing 67 the shaft `6l)4 is suitable fitted to receive a sprocket or the like for driving the shaft and pulley (this sprocket is not shown). The `arrowed line 72 represents the spacing between the shaft supporting bearings 67 and it is to be particularly noted that the central tubular member 24 extends to an adjacency ofA these supporting bearings and the conveyor stringer and thereby provide means to substantially eliminate the pulley loads causing shaft ilexure with the following advantages: (1A) Referring to the FIGURE 7 the spacing apart of the bearings 67 as represented by the arrowed line 72 relative to the spacing apart of the web means 23 are again independent of one another due entirely to the short distance between the bearing 60 and the outward ends of the central tubular member '24 substantially eliminating a moment arm that would cause shaft flexing by the pulley loadings disposed intermediate of the bea-rings, as a consequence (2A) provides that the shaft 60 be of a material smaller size than would be the case were the pulley hubs or the like disposed at the web means, as happens to be the prior practice concerning the production of wide face conveyor pulley arranged with a rotatable shaft for then unavoidable shaft ilexures take place, with the result (3A) that thereof these prior wide face conveyor pulley units that have their hubs for the shaft at each web means, it is a well established matter that with an increase of the distance between the pulley ends and the shaft support bearings even with an increase in the shaft size unavoidably results in a corresponding decrease in the allowable pulley load. Which is not the case thereof the present invention as it provides having the shaft bearing in an adjacency to that of thehub 61 at both ends of the tubular member 24, consequently, the allowable pulley loadings are unimpaired, resulting in (4A) over a wide range of conditions and conveyor sizes advantageously allows using a given size shaft, owing entirely to substantially eliminating shaft flexure situations, consequently (5A) provide for the use of corresponding smaller size bearings throughout a wide range of conditions and pulley sizes, that unquestionably results in (6A) cost savings, as a given development may be applied over a wide range of pulley sizes and conditions. (7A) and further in the central tubular member 2-4` being of size to accommodate the outside diameter of the hub 61 readily provides suilicient streng-th without encountering detrimental flexure situations. (8A) that the pulley be readily included into conveyor systems handling heavy class commodities while retaining its small shaft diameter size.

Now Ireferring to the FIGURES 8, 9 and 10, which,

shows the present invention arranged as a conveyor snub or bend pulley, which in practice are ordinarily of smaller diameter than head or tail pulleys. And with reference to the illustrations apply the same numeral with a suffix for similar parts. The arrowed line 25 represents the pulley diameter while the arrowed line 26" represents the face width of the pulley, which in conveyor practice ran-ges two or more inches greater than the normal width of the conveyor belt (not here shown). The numeral 22 represents the cylindrical rim of the pulley, while the numeral 23" represents the radial web means and 24 represents the central tubular member. Of which the web means 23 are welded to an internalportion of the rim 22 and an external portion of the central tubular member 24", all to form a single self-contained rigid pulley structure. And with particular reference to the FIGURE 9 which shows an enlarged section at each end of the central tubular member to show the mounting of tbe snub pulley ywith a nonrotating shaft 29". Each end of the central tubular member is bored for the bearing 30 and the seal members 31" and 32" which are held in place by the snap ring 33 and the shoulder 34". Both end portions of the shaft 29 are turned for the bearing 30 and to provide the shoulder 59". The bearing 30 of standard form includes its one way seal 37 and the shaft 29" projects beyond the central tubular member 24" and includes a flat face for the mounting clamp 74, which includes the pair of studs 75, best seen at the FIGURE 10. By means of dash lines indicate a fragmentary end view of a conveyor stringer 76 of which 73 is the gauge line while 77 indicates an angle clip that in practice would be welded to a web portion of the stringer to form a support for the snub pulley -unit as indicated at the FIGURES 9 and 10 by the mounting clamp 74. Each end of the shaft 29" is suitably fitted for the grease fitting 42 and the apertures 43 for delivery of the lubricant into the grease poc-ket 44" for lubrication of the bearing 30".

Now assuming that the pulley together with its shaft 29 having been suitably mounted operably, it is to be particularly noted that the pulley load disposed intermediate the pair of mounting clamps 74 is supported by the shaft 29 through the pair of bearings 30, each of which in turn are disposed within both end portions of the central tubular member 24" that extend beyond the ends of the pulley to a position in adjacency to the mounting clamp 74 with the following advantages (1B) referring to the FIGURE 8, the width spacing apart for the mounting clamps as represented by the arrowed line 78 between the clamp centers 80-and this width relative to that of the spacing apart of the radial web means 23 are independent of one another due to the short moment arm 79 which substantially causes elimination of the shaft 29 flexing, as a consequence (2B) provides that the shaft 2 be of material smaller size than would be the case were the bearing or the like disposed at the radial web means 23 as happens to be the prior practice concerning production of Wide face conveyor pulleys arranged with a stationary shaft for then unvoidably shaft flexures take place, with the result (3B) that thereof these prior wide face conveyor pulley units that have their shaft bearings disposed at each web means it is well established matter that with an increase of the distance between pulley ends and the shaft anchorages to the conveyor stringers and even with an increase in the shaft size unavoidably results in a corresponding decrease in the allowable pulley load. Which is not the case thereof the present invention as it provides having the shaft lbearing in adjacency to that of the clamping anchorages, consequently the allowable pulley loadings is unimpaired, resulting in (4B) over a wide range of conditions and conveyor sizes advantageously allows using a given size shaft, owing entirely to substantially eliminating shaft ilexure situations, consequently (5B) provide for the use of corresponding smaller size mounting clamp units throughout a wide range of conditions .and pulley sizes, that unquestionably results in (6B) cost savings, as a given development may be applied over a wide range of pulley sizes and conditions. (7B) And further in the central tubular member 24 being of size to accommodate the outside diameter of the shaft bearings 30: readily provides sufficient strength to allow using double row type bearings in place of the single row bearings 30 shown, with the end results (8B) that the pulley be readily included into conveyor systems handling heavy class cornmodities while retaining its small shaft size, for throughout the various applications the invention provides that shear governs shaft sizes instead of bending moment. (9B) In that the present invention provides a means which allows applying the same size shaft over a wide range of conditions, conveniently provides simple inexpensive methods to operably mount xedly and rigidly an entire pulley unit by the mounting clamp 74. None of which being provided thereof prior conveyor pulley units having stationary shafts, as they all must make provision for their unavoidable shaft flexure situations. (10B) Heretofore to provide conveyor snub or bend pulleys with bearings bolted to the pulley end webs for a nonrotating shaft, had to be made to order for the very valid reason that the size of the required shaft and corresponding size self-aligning anged cartridge bearing units was always an unknown factor prior to the receipt of a precise order. Therefore, the manufacturer was not in position to bore these end webs for the body portion of these costly flanged cartridge bearing units that extend through these web bores. Which also applies to the necessary bolting connections required. Then further the required shaft also has to be made to order. All of which involves very costly manufacture procedures as well as being very bothersome.

In that the present invention provides means to substantially eliminate shaft exure situations furnishes desirable feature whereby conveyor snub or bend pulleys with bearings and shaft may safely be produced in economical volume for stock purposes, from which the different size complete units can readily be marketed without the necessity of their having to made to order. And the very same desirable production features pertain as well to the shafts and mounting clamps units.

(llB) The present invention complies with t-he established standards concerning gauge spacings of the conveyor stringers for various size conveyor systems.

Various changes may be made in the embodiment of the invention hereinabove specifically described without departing from or sacrificing the advantages of the invention as dened in the appended claims.

I claim:

1. In combination, a cylindrical rim, a central tubular member, a spaced pair of web means, formed to provide a rigid conveyor pulley, by said cylindrical rim extending axially with said central tubular member extended parallel therethrough and beyond each end of said rim mounting an anti-friction bearing, said anti-friction bearing being disposed within each end portion of said tubular member, while each web means of radial form of said spaced pair of web means interconnect said rim and said member iixedly and form said rigid pulley.

2. The invention according to the claim 1 wherein, said anti-friction bearings forming support for said pulley on a stationary shaft as a unit, by said shaft projecting through said member and in adjacency each end of said shaft having surfaces for engaging adjacent support means to mount said unit operably, while said surfaces and said support means causes said shaft to remain stationary.

3. The invention according to claim 2 wherein, each end portion of said shaft having aperture means, said aperture means extend from each shaft end to an inclosed grease pocket, and said grease pocket being disposed in adjacency each said anti-friction bearing.

4. In combination, a cylindrical rim, a central tubular member, a spaced pair of web means, formed to provide a rigid conveyor pulley, by said cylindrical rim extend ing axially with said central tubular member extended parallel therethrough and beyond each end of said rim including a hub means, each said hub means having a bore, while each web means of radial form of said spaced pair of web means interconnect said rim and said member xedly and form said rigid pulley.

5. The invention according to the claim 4 wherein, said hub means forming support of said pulley on a shaft as a rigid unit, by said shaft projecting through said member while engaging said bore and in adjacency each end of sai-d member and said bore said shaft having an extension for engaging a journ-al means to mount said unit operably, while at least one said extension projects beyond said journal means for a driver means.

6. In combination, a cylindrical rim, a central tubular member, lat least a spaced pair of web means, formed to provide a rigid conveyor pulley, by each web means of radial form of said pair of web means interconnecting said rim and said member and wherein said cylindrical rim extending axially with said central tubular member extended parallel therethrough and beyond each end of said rim internally mounting an anti-friction bearing in adjacency to a spaced pair of conveyor stringer structures, said anti-friction bearings forming support for said pulley on a stationary shaft as a unit, by said shaft projecting through said member and said bearings and in adjacency each end of said member said shaft having Surfaces for engaging means to mount said unit operably by said structures, while said surfaces and said engaging means causes said shaft to rem-ain stationary.

7, The invention according to claim 6 wherein, end portions of said shaft having aperture means, said aperture means extend from the shaft end to an inclosed grease pocket, `and said grease pocket being disposed in adjacency said anti-friction bearings.

8. In combination, a cylindrical rim, a central tubular member, at least a spaced pair of web means, formed to provide a rigid conveyor pulley, by each web means of radial form of said spaced pair of web means interconnecting said cylindrical lrim and said central tubular member rigidly and wherein said cylindrical rim extending axially with said central tubular member extended parallel therethrough and beyond each end of said rim internally including a hub means in adjacency to a spaced pair of conveyor stringer structures, each said hub means having a bore, said hub means forming support of said pulley on a shaft as a rigid unit, by said shaft projecting through said member and said bore and in adjacency each end of said `member and said bore, said shaft having an extension for engaging a journal means to mount said unit operably by said structures, while at least one said extension projects beyond said journal means for a driver means.

9. In combination, a rim means, said rim means of cylindrical form extending axially, a central tubular member, a web means, formed to provide a rigid belt conveyor pulley, by said central tubular member having a continual axial length greater than said rim means and thereby cause its end portions extending beyond each end of said rim means while extended through both said rim and web means, wherein said web means of radial form disposed inter-mediate axially spaced portions of said rim means and said central tubular member and fixedly secured thereto to cause forming said rigid pulley*l 1t). The invention according to the claim 9 wherein, each end portion of said central tubular member including support means for engaging a shaft means, said shaft means projecting through and past each end of said central tubular member, so that said support means together with said shaft means form an operable support for said pulley. j

11. In a pulley for shafts of -belt conveyor mechanisms, each of said shafts being supported at points beyond the ends of said pulley, the combination with,

a cylindrical rim,

a hub adapted to be mounted on the shaft,

and web means connecting said rim and said hub,

the improvement of a tubular member of larger inner diameter than the shaft forming said hub, said tubular member extending axially through said rim and beyond the ends of said rim, support means at each end of the tubular member to support the tubular member on the shaft, thereby to vreduce the 9 leverage of the load exerted through said pulley onto said shaft,

and said web means between said rim and said tubular member being rigid.

12. The improvement defined in the claim 11, and said tubular member being of such length relatively to said shaft support points that said support means at the ends of said tubular ymember are adapted to be located in the proximity of said support points.

13. The improvement defined in the claim 11, wherein said support means consists of anti-friction bearings at the respective ends of said tubular member.

14. The improvement defined in claim 11, wherein said support means consists of a tubular plug in each end of References Cited UNITED STATES PATENTS Barker.

Cowley 308-20 Roberts.

Stephens.

Lee 30S-20 Doyer 193-37 X FRED C. MATTERN, IR., Primary Examiner.

DAVID I. WILLIAMOWSKY, Examiner.

the tubular member adapted to be secured on said shaft. 15 J' A WONG Assistant Examiner' 

1. IN COMBINATION, A CYLINDRICAL RIM, A CENTRAL TUBULAR MEMBER, A SPACED PAIR OF WEB MEANS, FORMED TO PROVIDE A RIGID CONVEYOR PULLEY, BY SAID CYLINDRICAL RIM EXTENDING AXIALLY WITH SAID CENTRAL TUBULAR MEMBER EXTENDED PARALLEL THERETHROUGH AND BEYOND EACH END OF SAID RIM MOUNTING AN ANTI-FRICTION BEARING, SAID ANTI-FRICTION BEARING BEING DISPOSED WITHIN EACH END PORTION OF SAID TUBULAR MEMBER, WHILE EACH WEB MEANS OF RADIAL FORM OF SAID SPACED PAIR OF WEB MEANS INTERCONNECT SAID RIM AND SAID MEMBER FIXEDLY AND FORM SAID RIGID PULLEY. 